docs: def _address_in_network(ip, netaddr, mask):
      """
      Like :func:`requests.utils.address_in_network` but takes a quad-dotted netmask.
      """
      ipaddr = struct.unpack('=L', socket.inet_aton(ip))[0]
      netmask = struct.unpack('=L', socket.inet_aton(mask))[0]
      network = struct.unpack('=L', socket.inet_aton(netaddr))[0] & netmask
      return (ipaddr & netmask) == (network & netmask)